TWI475519B - Photoelectric smoke detector - Google Patents

Description

Photoelectric smoke detector

The present invention relates to a photoelectric smoke detector, and more particularly to a configuration of a diaphragm disposed in front of a light emitting element.

Moreover, the present invention relates to a photoelectric smoke detector, and more particularly to a structure of a shield case that houses a light receiving element.

In the photoelectric smoke detector, a light-emitting element housing portion for accommodating a light-emitting diode (hereinafter also referred to as an LED) as a light-emitting element is provided in the dark box, and is provided in front of the light-emitting device for restricting the emission from the LED. The aperture in which the light travels.

In the photoelectric detector, the photodiode (hereinafter referred to as PD) as the light-receiving element absorbs smoke due to the weak scattered light caused by the smoke, so that it is not affected by electrical noise. Cover it with a shielded box. When the optical system including the PD is assembled, the PD is first inserted into the optical table and then inserted into the shielding box, and the components need to be individually mounted (see, for example, Patent Document 1).

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2003-141653

In the conventional photoelectric smoke detector, since only one aperture is provided, there is a problem that a certain amount of stray light cannot be removed.

Further, when the optical system of the conventional photoelectric smoke detector is assembled, as described above, since the PD and the shield case are individually processed and assembled, there is a problem that the number of man-hours for assembly increases.

The present invention has been developed in order to solve such a problem, and an object of the invention is to provide a photoelectric smoke detector capable of removing a certain amount of stray light.

Moreover, the present invention has been developed in order to solve such a problem, and an object of the invention is to provide a photoelectric smoke detector capable of reducing the number of man-hours when assembling an optical system.

The photoelectric smoke detector of the present invention is characterized in that a light-emitting element storage unit that houses a light-emitting diode as a light-emitting element and a photoelectric smoke detector that is disposed in a dark box in front of the light-emitting element storage unit are characterized in that The aperture is formed by a plurality of apertures having different distances from the light-emitting diode, and an aperture diameter of the plurality of apertures is formed to be proportional to a distance from the light-emitting diode. Become bigger.

In the photoelectric smoke detector of the present invention, the plurality of apertures are formed on the optical table side of the dark box, and the openings are formed to be different from each other in the lower side and the upper side in the opening.

Further, the photoelectric smoke detector of the present invention is a light-detecting element accommodating portion in a dark box, and houses a light-receiving element and a photoelectric sound-detecting device that covers a cylindrical shield case of the light-receiving element, and is on the back side of the shield case. A pressing spring portion that pushes and pushes the light receiving element toward the front side.

Further, in the photoelectric smoke detector of the present invention, the shield case is formed by bending a single plate.

According to the present invention, since the aperture is composed of a plurality of apertures different in distance from the light-emitting diode, the aperture diameter of the plurality of apertures is formed to be a distance from the light-emitting diode. Since it is proportionally enlarged, from the light-emitting diode, light is contracted by a plurality of apertures, and a certain amount of stray light is removed.

According to the present invention, since a plurality of apertures are formed on the optical table side of the dark box, the openings are formed to be different from each other in the lower side and the opening on the upper side. Therefore, the mold structure during resin molding can be utilized. A plurality of apertures are formed at an increased cost, which can improve the aperture effect.

Further, in the present invention, the back surface of the shield case is provided with a pressing spring portion that is pushed inward and presses the light receiving element toward the front side, and the light receiving element is pressed by the pressing spring portion to integrate the light receiving element with the shield case. Therefore, the integrated light receiving element can be inserted into the light receiving element housing portion of the optical system simultaneously with the shield case. Therefore, it is possible to reduce the number of man-hours when assembling the optical system. Further, when the photoelectric smoke detector is used, since the light receiving element is pressed by the pressing spring portion, the light receiving element does not rattle inside the shield case.

Further, in the present invention, since the shield case is formed by bending one plate, the number of parts for manufacturing the shield case can be small, and the manufacturing can be easily performed.

Fig. 1 (a) and (b) are an external view of a photoelectric smoke detector according to an embodiment of the present invention, and a cross-sectional view taken along line b-b. 2 and 3 are exploded perspective views of the photoelectric smoke detector of Fig. 1, wherein Fig. 2 is a perspective view when viewed from above, and Fig. 3 is a perspective view when viewed from below. Furthermore, in FIG. 1(b), a part of the internal components is omitted.

The photoelectric smoke detector includes a main body 1 (not shown) for mounting an alarm speaker for driving a fire or the like, a cover covering the main body 1 (protective cover) 2, and a main body 1 The mounting plate 3 attached to the mounting screw hole or the like on the back surface has a black box 4 that is a component (details will be described later) that functions as a smoke detecting unit between the main body 1 and the lid 2. The cover 2 is provided at the upper portion thereof with a plurality of smoke inflow windows 21 for feeding in and out of the smoke to be detected, and an opening portion 23 for projecting one of the buttons 22. The button 22 is rotatably supported by the inner wall of the cover 2 at one end, and the other end is locked. By pressing the portion protruding from the opening 23, the touch switch 42 to be described later is activated. Further, an alarm speaker 24 (see Fig. 3) is attached to the inner wall of the cover 2.

The main body 1 is composed of a disk-shaped substrate 113 and a peripheral wall 114 that is erected on the outer peripheral edge of the outer peripheral edge thereof. The upper edge portion (on the side of the mounting plate 3) of the peripheral wall 114 is provided to extend inwardly and inwardly. The pair of flat blade portions 115a and 115b of the engaging portion are formed with through holes 116a and 116b for the overcut portions of the blade portions 115a and 115b directly under the blade portions 115a and 115b of the substrate 113.

The cover 2 is composed of a substantially mountain-shaped bowl portion 121 and a peripheral wall 123 provided on the outer peripheral edge thereof, and is provided inside the peripheral wall 123 corresponding to the through holes 116a and 116b formed in the substrate 113 of the main body 1. Approximate The shape and cylindrical surrounding walls 124a, 124b have a height at which the front end portion abuts or approaches the substrate 113 of the body 1 when the cover 2 is assembled to the body 1. Further, the main body 1 and the cover 2 integrally coupled to the main body 1 by a plurality of screws are used to constitute the alarm main body 100 as the sensor main body.

The mounting plate 3 has a disk-shaped substrate 132, a peripheral wall 133 provided on the main body 1 side of the outer peripheral edge of the substrate 132, and an inner wall 134 disposed concentrically with the peripheral wall 133, and is disposed in the upper edge portion of the inner wall 134. The blade receiving portions 135a and 135b that are extended toward the outer peripheral side and that are spaced apart from the peripheral wall 133 by the gap g are provided at positions corresponding to the blade portions 115a and 115b provided in the main body 1.

The black box 4 has a printed circuit board 41 attached to the lower portion thereof, and a touch switch 42 is attached to the printed circuit board 41. The touch switch 42 is turned ON by the operation of the button 22 described above. Further, the button 22 is operated to detect smoke while the alarm speaker 24 is sounded and is being repaired. The detailed structure of this dark box 4 will be explained in more detail based on Fig. 4.

4 is an exploded perspective view of the dark box 4.

The dark box 4 is composed of an optical table 43 and an optical table cover 44 that covers the optical table 43. The optical table 43 is provided with a light-emitting element housing portion 45, a light-receiving element housing portion 46, and a plurality of labyrinth members 47. The light-receiving element accommodating portion 46 is disposed such that the light emitted from the light-emitting element accommodating portion 45 is not directly incident on the light-emitting element accommodating portion 45. A light-emitting element such as a bullet-type LED 60 is attached to the light-emitting element housing portion 45. Further, the PD 49 accommodated in the shield case 48 is attached to the light receiving element housing portion 46. In the optical table cover 44, a plurality of smoke inlets and outlets 44a are formed, and an insect net 44b is provided in the smoke inlet and outlet 44a to prevent foreign matter such as insects from entering the dark box 4.

Fig. 5 is a view showing a detailed structure of the optical table 43, (a) is a front view, (b) is a plan view, (c) is a cc sectional view of (b), and (d) is a dd cross section of (a) Fig., (e) is a side view, and (f) is a bottom view.

6 is a perspective view showing a detailed configuration of a diaphragm formed in front of the LED 60, and FIG. 7 is a cross-sectional view showing a peripheral portion of the LED 60 in a cross-sectional view of FIG. 5(c).

The LED 6 is attached to the light-emitting element housing portion 45, but the first diaphragm 61 and the second diaphragm 62 are formed on the optical table 43 in front of each other. The first aperture 61 has a shape in which a circular shape and a shape in which a lower portion of the circular portion is opened are combined. Further, the second aperture 62 has a shape in which a circular shape and a shape in which the circular portion is opened upward are combined. In FIG. 6, the shape of the second diaphragm 62 is clearly shown, and the first diaphragm 61 has a shape in which the shape of the second diaphragm 62 of FIG. 6 is reversed in the vertical direction. Further, the first aperture 61 and the second aperture 62 are formed such that their opening diameters (width directions) become larger in proportion to the distance from the LEDs 60.

Fig. 8 is an explanatory view of the operation of the aperture.

The aperture formed in front of the LED 60 functions to contract the light emitted from the LED 60, but the light in contact with the aperture is scattered and travels in a predetermined outward direction. However, the apertures 61 and 62 of the present embodiment are formed in a double shape, and the light reflected by the peripheral member 61a of the first aperture 61 located on the front side when viewed from the LED 60 is reflected by the first aperture 61 and viewed from the LED 60. The peripheral member 62a of the second diaphragm 62 at the time of separation is in contact with and reflected, and the light reflected by the first diaphragm 61 can be contracted.

Further, since the opening diameter (width direction) of the first diaphragm 61 and the second diaphragm 62 is formed to be proportional to the distance from the LED 60, the light emitted from the LED 60 is as shown in FIG. It is appropriately contracted and travels in a predetermined direction to illuminate the inside of the dark box 4.

Further, the first aperture 61 has a shape in which a circular shape is combined with a shape in which a lower portion of the circular portion is opened, and the second aperture 62 is formed by combining a circular shape and a shape of an opening above the circular portion. The shape is a shape that is open below or above. However, since the LED 60 and the PD 49 have a positional relationship with respect to the horizontal direction, even if scattered light in the vertical direction is generated, the scattered light can be ignored, and scattering in the horizontal direction (horizontal direction) can be restricted. Light can be used, so there is no hindrance to the shape that is open below or above.

Fig. 9 is a view showing a detailed configuration of the shield case 48, wherein (a) is a front view, (b) is a right side view, (c) is a rear view, and (d) is a bottom view.

The shielding box 48 is formed by cutting and bending a piece of sheet material into a cylindrical shape, and is composed of a front panel 50, an upper panel 51, a back panel 52, and side panels 53, 54. The front panel 50 and the upper panel 51 and the back panel 52 are formed. In a continuous shape, the front panel 50 and the side panels 53 and the side panels 54 are also continuous. An opening 50a is formed in an upper portion of the front panel 50, and the scattered light is supplied to the built-in PD 49 via the opening 50a. A pair of tongue pieces 53a, 53b, 54a, and 54b are formed in the side portions of the side plates 53 and 54 on the back panel side in the vertical direction. On both sides of the tongue pieces 53b, 54b, notches 53c, 54c are formed, respectively, so that the tongues 53b, 54b are easily bent, and the upper side of the state in which the tongue pieces 53b, 54b are bent and the ends of the tongue pieces 53b, 54b are provided. The department becomes the same. In a state in which the tongue pieces 53b and 54b are bent toward the back panel side (the bending position is a position further inside than the end portions of the side panels 53 and 54), the back panel 52 is bent on the upper surface. Further, in this state, the back panel 52 is fixed by the bent tongues 53a and 54a. That is, the back surface plate 52 is held by the tongue pieces 53a, 54a and the tongue pieces 53b, 54b and held so that no gap is formed between the back surface plate 52 and the side plates 53 and 54. Further, the side plates 53 and 54 are formed with convex portions 53d and 54d that protrude inward at positions corresponding to the lower portion of the PD 49, and are used to hold the PD 49 together with the pressing spring portion 52a to be described later.

In the back panel 52 of the shield case 48, a pressing spring portion 52a whose portion is vertically long and has three sides cut away and which is bent toward the front panel 50 side is formed. This presses the PD 49 toward the front panel 50 side. Further, a mounting portion 52b for inserting into the light receiving element housing portion 46 and attached to the printed circuit board 41 is provided in a lower portion of the back surface plate 52. Further, from the lower portion of the shield case 48, in addition to the mounting portion 52b, the terminal 49a of the PD 49 protrudes downward and is presented.

The shield case 48 configured as described above and the PD 49 housed in the shield case are integrally held and held in the light receiving element housing portion 46 as shown in FIG. 4, and are fixed to the printed circuit board 41 by soldering or the like.

The photoelectric smoke detector of the present embodiment is configured as described above, and causes the LED 60 to emit light to monitor the fire monitoring. However, normally (normal), the light of the LED 60 does not enter the PD 49. When an abnormality occurs, that is, when a fire occurs, the smoke flows into the window 21 through the smoke inflow port 44a, and flows into the dark box 4, colliding with the light from the LED 60, and thus the traveling path of the light changes, and a part of the scattered light is changed. Enter the PD49. When the scattered light entering the PD 49 exceeds a predetermined amount, the alarm speaker 24 is sounded by the control not shown.

Further, in the present embodiment, the apertures 61 and 62 are composed of a plurality of apertures having different distances from the LEDs 60, and the apertures (width directions) of the plurality of apertures are formed to be proportional to the distance from the LEDs 60. Since the ground becomes large, the light from the LED 60 is contracted by the plurality of apertures 61 and 62, and a certain amount of stray light is removed. Further, since the first and second apertures 61 and 62 are formed on the optical table 43 side of the dark box 4, the first aperture 61 opened on the lower side and the aperture formed on the upper aperture 62 are different from each other. For example, a plurality of apertures can be formed by sandwiching two molds by using a mold structure during resin molding, which is not only easy to manufacture, but also forms a plurality of apertures 61 and 62 without increasing the cost. Further, it is also possible to exert a function of tightening the light emitted from the LED 60 in the up and down direction.

In the above description, the first diaphragm 61 is opened on the lower side, and the second diaphragm 62 is on the upper side as an example. However, the reverse may be reversed. That is, the first diaphragm 61 is opened to the upper side, and the second diaphragm 62 is opened to the lower side. Further, since the aperture of the present invention can restrict the stray light in the horizontal direction (horizontal direction), the apertures 61 and 62 can be optimally combined with the intended purpose, and for example, can be used as a triple structure.

Further, in the present embodiment, since the PD 49 is held by the convex portions 53d and 54d of the side plates 53 and 54 of the shield case 48 and the pressing spring portion 52a, these portions can be handled as one component and assembled. It can reduce its working hours. Further, even when the photoelectric smoke detector is used, since the PD 49 is pressed by the pressing spring portion 52a of the shield case 48, the PD 49 does not shake inside the shield case 48. Further, since the shield case 48 is formed by cutting and bending one piece of the sheet material, it is possible to avoid an increase in the number of parts, and the number of parts for manufacturing the shield case 48 is small, which makes it easy to manufacture.

In the above description, the PD 49 is held by the convex portions 53d and 54d of the side plates 53 and 54 of the shield case 48 and the pressing spring portion 52a. However, the present invention is not limited thereto, and may be borrowed only. The PD 49 is held by the pressing spring portion 52a.

Further, in the above-described embodiment, the photoelectric fire detector has been described as a fire alarm for a house. However, the present invention is not limited thereto, and a fire detector connected to a fire receiver via a signal line or the like may be applied. this invention.

Next, the surrounding walls 124a and 124b will be described. The surrounding walls 124a and 124b are members provided on the cover 2 for the purpose of preventing the screws or the like from falling into the alarm body 100 from the through holes 116a and 116b formed in the main body 1 during assembly.

Next, an example of the assembly of the fire alarm of the above configuration and the mounting procedure for the ceiling or the like will be described. Further, the cover 2 is a member to which the printed circuit board 41, the alarm speaker 24, the button 22, and the like are mounted.

First, the peripheral wall 123 of the cover 2 is fitted to the outer circumference of the main body 1, and the screw inserted into the screw insertion hole 119 of the main body 1 is screwed into the screw hole 129 of the cover 2, and the two are integrated and assembled.

The state at this time is as shown in FIG. 10 (further, in the following description, a and b of the symbol are omitted). As shown in the figure, the through hole 116 provided in the substrate 113 of the main body 1 is sealed by the surrounding wall 124 provided in the cover 2, and is blocked from the inside of the alarm main body 100 having the printed circuit board 41 or the like.

The alarm body 100 thus assembled is fitted to the ceiling by screwing the blade portions 115a and 115b of the main body 1 in the circumferential direction from the blade receiving portions 135a and 135b. After the mounting plate 3 is mounted, the alarm body 100 is rotated in the circumferential direction, and the blade portions 115a and 115b are locked to the blade receiving portions 135a and 135b, and are attached to the mounting plate 3. The state at this time is as shown in FIG.

When the alarm body 100 is removed from the mounting plate 3, the alarm body 100 is rotated in the opposite direction, and the blade portions 115a, 115b are detached from the blade receiving portions 135a, 135b.

According to the present embodiment configured as described above, even if small parts such as screws fall into the through holes 116a and 116b of the body 1, they stay in the surrounding walls 124a and 124b and do not enter the alarm body 100. Therefore, the excessive decomposition work for removing the small parts is not generated, and therefore, the assembly work efficiency can be improved.

In addition, since the screw or the like is not lost in the alarm body 100, the insects, dust, and the like cannot enter the alarm body 100 from the through holes 116a and 116b after being installed in a house or the like. High reliability fire alarm.

Further, the case where the through holes 116a and 116b provided in the substrate 113 of the main body 1 are sealed by the surrounding walls 124a and 124b provided in the cover 2 is shown, but it may be used to seal the through holes as shown in FIG. The surrounding wall 125 of 116a, 116b is disposed on the body 1.

In other words, on the surface of the main body 1 on the side opposite to the blade portion 115 of the substrate 113, at least the edge portion on the center portion side and the edge portions on both sides of the through hole 116 are provided when the cover 2 is assembled. When the main body 1 is at the height, the front end portion is connected to or close to the inner wall surface of the cover 2 to surround the wall 125. In addition, in FIG. 12, the surrounding wall 125a provided in the edge part opposite to the edge part of the center part side of the through-hole 116 may also be deleted.

As described above, the fire alarm device includes the blade portions 115a and 115b having the engaging portions that are erected on the back surface of the substrate 113 and facing inward, and the engaging portions 115a and 115b of the substrate 113 are positive. a body 1 having a through hole 116a, 116b formed below, and an alarm body 100 having a bowl portion 121 integrally coupled to the cover 2 of the body 1; and having an engagement portion with the alarm body 100 The blade receiving portions 135a and 135b of the engaged portions 115a and 115b are fixed to the mounting plate 3 such as a ceiling surface, and the cover 2 is provided on the inner wall surface toward the main body 1 side and surrounds the main body 1 The through holes 116a and 116b surround the walls 124a and 124b.

Further, in the fire alarm, the surrounding walls 125a and 125b which are erected toward the cover 2 side are provided on the front side of the through holes 116a and 116b formed in the substrate 113 of the main body 1, instead of the surrounding wall provided on the cover 2 124a, 124b.

Since the above structure is provided, there is no possibility that a small object such as a screw falls into the alarm body 100, so that unnecessary disassembly work is not required, and assembly work efficiency can be improved.

In addition, since the screw or the like is not lost in the alarm body 100, the insects, the dust, and the like cannot enter the alarm body 100 from the through hole after being installed in a house or the like, so that high reliability can be obtained. Alarm.

In the above description, the present invention has been described with respect to the illustrated fire alarm. However, the present invention is not limited thereto, and the present invention may be implemented in a fire alarm of another configuration. Further, the present invention can be implemented by using another alarm device that uses another detection unit, such as a gas leakage alarm of a gas detecting unit, as the detecting unit.

1. . . Ontology

2. . . cover

3. . . Mounting plate

4. . . Black box

twenty one. . . Smoke into the window

twenty two. . . Button

twenty three. . . Opening

twenty four. . . Alarm speaker

41. . . Printed substrate

42. . . Touch switch

43. . . Optical table

44. . . Optical table cover

44a. . . Smoke entrance

44b. . . Insect net

45. . . Light-emitting element storage unit

46. . . Light-receiving element storage unit

47. . . Labyrinth component

48. . . Shield box

49. . . PD

50. . . Positive panel

50a. . . Opening

51. . . On board

52. . . Back panel

52a. . . Pressing the spring

52b. . . Installation department

53, 54, . . Side panel

53a, 53b, 54a, 54b. . . Tab

53d, 54d. . . Convex

60. . . led

61. . . First aperture

62. . . Second aperture

100. . . Alarm body

113. . . Substrate

114. . . Zhou wall

115, 115a, 115b. . . Blade (engagement)

116a, 116b. . . Through hole

119. . . Screw insertion hole

121. . . Bowl

123. . . Zhou wall

124, 124a, 124b, 125, 125a, 125b. . . Surrounding wall

129. . . Screw hole

132. . . Substrate

133. . . Zhou wall

134. . . Inner wall

135a, 135b. . . Blade receiving part (engaged part)

136a, 136b. . . Screw insertion hole

Fig. 1 (a) and (b) are an external view of a photoelectric smoke detector according to an embodiment of the present invention, and a cross-sectional view taken along line b-b.

2 is an exploded perspective view of the photoelectric smoke detector of FIG. 1.

3 is an exploded perspective view of the photoelectric smoke detector of FIG. 1.

Figure 4 is an exploded perspective view of the black box.

5(a) to 5(f) are diagrams showing the detailed structure of the optical table.

Fig. 6 is a perspective view showing a detailed structure of an aperture formed in front of the LED.

Fig. 7 is a cross-sectional view showing a peripheral portion of the LED of Fig. 5(c).

Fig. 8 is an explanatory view of the operation of the aperture.

9(a) to 9(d) are diagrams showing the detailed structure of the shield case.

Figure 10 is a partial cross-sectional view showing the state after the cover is assembled to the body.

Fig. 11 is a partial cross-sectional view showing a state in which the alarm body of Fig. 10 is attached to a mounting plate.

Fig. 12 is a partial cross-sectional view showing a state in which the alarm body is attached to the mounting plate (variation).

43. . . Optical table

60. . . led

61. . . First aperture

62. . . Second aperture

Claims (2)

A photoelectric smoke detector is a photoelectric smoke detector in which a light-emitting element housing portion that is a light-emitting diode of a light-emitting element and a diaphragm that is disposed in front of the light-emitting element housing portion are formed in a dark box, and is characterized in that The aperture is formed by a plurality of apertures having different distances from the light-emitting diode, and an aperture diameter of the plurality of apertures is formed to be proportional to a distance from the light-emitting diode. Become bigger. The photoelectric smoke detector according to claim 1, wherein the plurality of apertures are formed on an optical table side of the dark box, and the openings are different from each other in the lower side and the upper side in the opening.